RFR: Update remembered set during old generation mark

[earthling-amzn]

On Wed, 21 Apr 2021 13:10:51 GMT, Zhengyu Gu <zgu at openjdk.org> wrote:

>> This change is to support the concurrent remembered set scanning work which is in progress.
>
> src/hotspot/share/gc/shenandoah/shenandoahMark.inline.hpp line 278:
> 
>> 276:       // Old mark, found a young pointer.
>> 277:       assert(ShenandoahHeap::heap()->is_in_young(obj), "Expected young object.");
>> 278:       ShenandoahHeap::heap()->mark_card_as_dirty((HeapWord*)p);
> 
> Just a nit, please use cast_from_oop<HeapWord*>(p) instead.

Sure, will fix this.

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PR: https://git.openjdk.java.net/shenandoah/pull/31